Flow sensor and flow resistive element

Abstract

A flow sensor is disclosed that measures a flow of fluid passing through a conduit and a flow resistive element for use in such a flow sensor. The flow sensor includes a housing having a main channel defined therethrough. A flow resistive element is disposed in the housing across the main channel. The flow resistive element includes a rigid body member having a first surface and a second surface. A plurality of unobstructed, wedge-shaped, openings are defined in the body member and extend through the rigid body member. In addition, a plurality of spokes extend from a central portion of the body member to its perimeter so that each spoke separates adjacent wedge-shaped openings from one another.

1. A flow sensor adapted to be positioned in a fluid carrying conduit to measure a flow of fluid passing through the conduit, comprising:
 (1) a housing having a first end, a second end, and a main channel defined through the housing between the first end and the second end, wherein the main channel includes a longitudinal axis, and wherein the first and the second ends of the housing are adapted to be coupled to the conduit so that fluid passes through the housing along the main channel between the first end and the second end; 
 (2) a flow resistive element coupled to the housing such that the flow resistive element does not rotate relative to the housing and traverses the main channel, wherein the flow resistive element comprises:
 (a) a rigid body member fixed to the housing and having a first surface and a second surface, 
 (b) a plurality of unobstructed, wedge-shaped, openings defined in the body member and extending therethrough from the first surface to the second surface, and 
 (c) a plurality of spokes extending from a central portion of the body member to a perimeter thereof, wherein each spoke separates adjacent wedge-shaped openings from one another; 
 
 (3) a first port defined through the housing to communicate a sensor element with the main channel on a first side of the flow resistive element; and 
 (4) a second port defined through the housing to communicate the sensor element with the main channel on a second side of the flow resistive element opposite the first side. 
 
   
   
     2. The flow sensor of  claim 1 , wherein the plurality of wedge-shaped openings are uniform in size and shape. 
   
   
     3. The flow sensor of  claim 1 , wherein the plurality of wedge-shaped openings are defined through the body member in a direction that is substantially parallel to the longitudinal axis of the main channel. 
   
   
     4. The flow sensor of  claim 1 , wherein the first surface is substantially planar and is disposed in a first plane that is substantially perpendicular to the longitudinal axis, and wherein the second surface is substantially planar and is disposed in a second plane that is also substantially perpendicular to the longitudinal axis. 
   
   
     5. The flow sensor of  claim 1 , wherein each wedge-shaped opening in the plurality of wedge-shaped openings includes an apex portion, and wherein the plurality of wedge-shaped openings are defined in the rigid body member such that the apexes of the plurality of wedge shaped openings are located proximate to a center of the rigid body member. 
   
   
     6. The flow sensor of  claim 1 , wherein the plurality of wedge-shaped openings include a first set of first wedge-shaped openings each having a first area and a second set of second wedge-shaped openings each having a second area that is greater than the first area, and wherein adjacent second wedge-shaped openings are separated from one another by at least one first wedge-shaped opening. 
   
   
     7. The flow sensor of  claim 1 , further comprising a central opening defined through the rigid body member generally at a central location of the rigid body. 
   
   
     8. The flow sensor of  claim 7 , wherein the central opening has a generally circular shape and is defined through the rigid body member in a direction that is substantially parallel to the longitudinal axis of the main channel. 
   
   
     9. The flow sensor of  claim 1 , wherein the housing comprises a first housing portion and a second housing portion having an identical structure, and wherein the first and the second housing portions include an locking assembly that selectively couples the first housing portion to the second housing portion. 
   
   
     10. The flow sensor of  claim 1 , further comprising a first averaging ring disposed on the first side of the flow resistive element such that a first chamber is defined between the first averaging ring and a portion of the housing, and a second averaging ring disposed on a second side of the flow resistive element such that a second chamber is defined between the first averaging ring and a portion of the housing, wherein the first port communicates with the first chamber and the second port communicates with the second chamber, and wherein the first and the second averaging rings include a plurality of openings defined therein to communicate the first and the second chambers with the main channel. 
   
   
     11. The flow sensor of  claim 1 , further comprising:
 a first wall disposed on the first side of the flow resistive element, wherein the first wall defines a first chamber on the first side of the flow resistive element, wherein the first chamber communicates with the main channel via at least one first chamber communication port defined in the first wall, and wherein the first port communicates with the first chamber; and 
 a second wall disposed on the second side of the flow resistive element, wherein the second wall defines a second chamber on the second side of the flow resistive element, wherein the second chamber communicates with the main channel via at least one second chamber communication port defined in the second wall, and wherein the second port communicates with the second chamber. 
 
   
   
     12. The flow sensor of  claim 11 , wherein the first chamber communication port, the second chamber communication port, the first port, and the second port are all disposed on one side of the longitudinal axis of the flow sensor. 
   
   
     13. A flow resistive element comprising:
 a rigid body member having a first surface and a second surface and a longitudinal axis, 
 a plurality of unobstructed, wedge-shaped, openings defined in the body member and extending therethrough from the first surface to the second surface, and 
 a plurality of spokes extending from a central portion of the body member to a perimeter thereof, wherein each spoke separates adjacent wedge-shaped openings from one another, wherein the plurality of wedge-shaped openings include a first set of first wedge-shaped openings each having a first area and a second set of second wedge-shaped openings each having a second area that is greater than the first area, and wherein adjacent second wedge-shaped openings are separated from one another by at least one first wedge-shaped opening. 
 
   
   
     14. The flow resistive element of  claim 13 , wherein the plurality of wedge-shaped openings are uniform in size and shape. 
   
   
     15. The flow resistive element of  claim 13 , wherein the plurality of wedge-shaped openings are defined through the body member in a direction that is substantially parallel to the longitudinal axis of the body member. 
   
   
     16. The flow resistive element of  claim 13 , wherein the first surface is substantially planar and is disposed in a first plane that is substantially perpendicular to the longitudinal axis, and wherein the second surface is substantially planar and is disposed in a second plane that is also substantially perpendicular to the longitudinal axis. 
   
   
     17. The flow resistive element of  claim 13 , wherein each wedge-shaped opening in the plurality of wedge-shaped openings includes an apex portion, and wherein the plurality of wedge-shaped openings are defined in the rigid body member such that the apexes of the plurality of wedge shaped openings are located proximate to a center of the rigid body member. 
   
   
     18. The flow resistive element of  claim 13 , further comprising a central opening defined through the rigid body member generally at a central location of the rigid body. 
   
   
     19. The flow resistive element of  claim 18 , wherein the central opening has a generally circular shape and is defined through the rigid body member in a direction that is substantially parallel to the longitudinal axis of the main channel. 
   
   
     20. A flow sensor adapted to be positioned in a fluid carrying conduit to measure a flow of fluid passing through the conduit, comprising:
 (1) a housing having a first end, a second end, and a main channel defined through the housing between the first end and the second end, wherein the main channel includes a longitudinal axis, and wherein the first and the second ends of the housing are adapted to be coupled to the conduit so that fluid passes through the housing along the main channel between the first end and the second end; and 
 (2) a flow resistive element disposed in the housing so as to traverse the main channel, wherein the flow resistive element comprises:
 (a) a rigid body member having a first surface and a second surface, 
 (b) a plurality of unobstructed, wedge-shaped, openings defined in the body member and extending therethrough from the first surface to the second surface, and 
 (c) a plurality of spokes extending from a central portion of the body member to a perimeter thereof, wherein each spoke separates adjacent wedge-shaped openings from one another, wherein the plurality of wedge-shaped openings include a first set of first wedge-shaped openings each having a first area and a second set of second wedge-shaped openings each having a second area that is greater than the first area, and wherein adjacent second wedge-shaped openings are separated from one another by at least one first wedge-shaped opening. 
 
 
   
   
     21. A flow sensor adapted to be positioned in a fluid carrying conduit to measure a flow of fluid passing through the conduit, comprising:
 (1) a housing having a first end, a second end, and a main channel defined through the housing between the first end and the second end, wherein the main channel includes a longitudinal axis, and wherein the first and the second ends of the housing are adapted to be coupled to the conduit so that fluid passes through the housing along the main channel between the first end and the second end; 
 (2) a flow resistive element disposed in the housing so as to traverse the main channel, wherein the flow resistive element comprises:
 (a) a rigid body member having a first surface and a second surface, 
 (b) a plurality of unobstructed, wedge-shaped, openings defined in the body member and extending therethrough from the first surface to the second surface, and 
 (c) a plurality of spokes extending from a central portion of the body member to a perimeter thereof, wherein each spoke separates adjacent wedge-shaped openings from one another; 
 
 (3) a first port defined through the housing to communicate a sensor element with the main channel on a first side of the flow resistive element; 
 (4) a second port defined through the housing to communicate the sensor element with the main channel on a second side of the flow resistive element opposite the first side; 
 (5) a first averaging ring disposed on the first side of the flow resistive element such that a first chamber is defined between the first averaging ring and a portion of the housing; and 
 (6) a second averaging ring disposed on a second side of the flow resistive element such that a second chamber is defined between the first averaging ring and a portion of the housing, wherein the first port communicates with the first chamber and the second port communicates with the second chamber, and wherein the first and the second averaging rings include a plurality of openings defined therein to communicate the first and the second chambers with the main channel. 
 
   
   
     22. A flow sensor adapted to be positioned in a fluid carrying conduit to measure a flow of fluid passing through the conduit, comprising:
 (1) a housing having a first end, a second end, and a main channel defined through the housing between the first end and the second end, wherein the main channel includes a longitudinal axis, and wherein the first and the second ends of the housing are adapted to be coupled to the conduit so that fluid passes through the housing along the main channel between the first end and the second end; 
 (2) a flow resistive element disposed in the housing so as to traverse the main channel, wherein the flow resistive element comprises:
 (a) a rigid body member having a first surface and a second surface, 
 (b) a plurality of unobstructed, wedge-shaped, openings defined in the body member and extending therethrough from the first surface to the second surface, and 
 (c) a plurality of spokes extending from a central portion of the body member to a perimeter thereof, wherein each spoke separates adjacent wedge-shaped openings from one another, 
 
 (3) a first port defined through the housing to communicate a sensor element with the main channel on a first side of the flow resistive element; 
 (4) a second port defined through the housing to communicate the sensor element with the main channel on a second side of the flow resistive element opposite the first side; 
 (5) a first wall disposed on the first side of the flow resistive element, wherein the first wall defines a first chamber on the first side of the flow resistive element, wherein the first chamber communicates with the main channel via at least one first chamber communication port defined in the first wall, and wherein the first port communicates with the first chamber; and 
 (6) a second wall disposed on the second side of the flow resistive element, wherein the second wall defines a second chamber on the second side of the flow resistive element, wherein the second chamber communicates with the main channel via at least one second chamber communication port defined in the second wall, and wherein the second port communicates with the second chamber.